Question

Describe the method of plotting pile load test data to determine pile design capacity.

Answer 1

Pile load test is done to determine the pile design capacity i.e to determine settlement of pile under working load. This test is suitable to determine the footing size of any structure as per settlement.

Method of plotting pile load test data :

i) As first in the pile load test, the load applied on the pile is in equal increment of about 20% of the allowable load. Then settlement is checked after the load increment of 0.5,1,2,4, 8, 12,16,20, 60 minutes. Twice of the safe load or under which load settlement is maximum that is observed.

ii) Then under each load, settlement is observed and a load-settlement curve is plotted to determine Ultimate load capacity (Qu) of pile. The allowable load or safe load is taken one-half of ultimate load.

Settlement is taken in mm.